Add missing files

Author: sparkprime

python/testdata/basic_check.jsonnet

@@ -0,0 +1,5 @@
+std.assertEqual(({ x: 1, y: self.x } { x: 2 }).y, 2) &&
+std.assertEqual(std.native("concat")("foo", "bar"), "foobar") &&
+std.assertEqual(std.native("return_types")(), {a: [1, 2, 3, null, []], b: 1, c: true, d: null, e: {x: 1, y: 2, z: ["foo"]}}) &&
+true
+

python/testdata/trivial.jsonnet

@@ -0,0 +1,2 @@
+// used for testing imports
+42